System for operating trains



July 19, 1938. A. e. SHAVER SYSTEM FOR OPERAIING TRAINS Original Filed April 15, 1932 2 Sheets-Sheet 1 S an INVEN'T'OR ARCH [BALD G -HAVER July 19, .1938.

A. G. SHAVER SYSTEM FOR OPERATING TRAINS 2 Sheets-Sheet 2 Original Filed April 15, 1932 IN'VENTOR ARCHIE 5%.?

ALD G SHAVER A TO Patented July 19, 1938 UNITED STATES- PATENT OFFICE Application April 15, 1932, Serial No. 605,38li Renewed March 3, 1937 41 Claims.

This invention relates to a system for operating trains, and more particularly to means for the operation of trains over a track switch and indieating on the trains and in the office of the train dispatcher the position of the switch; and has special reference to the provision of a system for the operation of track switches in a dispatchers district jointly by the trains and the dispatcher, and inductively indicating both the normal and reverse positions of a switch, through means associated with the switch and means carried on the trains and in the dispatchers oflice in connection with means for communication between the head end and rear end of trains and between the trains and the dispatcher.

In the system of communication referred to, the

stretch of track in the dispatchers district is sectionalized and an electrically independent intermediate or loop circuit is provided for each section or group of sections. Transmitting and receiving communication sets are provided in the dispatchers oflice and on the trains, same being adapted for communicative relationship with said intermediate circuits as the train proceeds through the stretch. Adjacent loop circuits are arranged to be communicatively connected when the train passes from one corresponding section to the adjacent corresponding section. Communication sets may be located in both the locomotive and caboose for communication to be carried on between the engineman and the conductor as well as between either or both of these persons and the dispatcher. Selector controlling means in the dispatchers ofiice permits of the dispatcher connecting the loop circuits with the communication circuit connected to his office; also, the selector controlling means permits of the control of devices at the track switches so that a track switch may be opened (reversed) on the approach of a train and closed (returned to normal position) after the train has passed over the switch. A circuit switch, connected with for operation by the track switch, controls a circuit at the track switch containing a transmitting device, said device being operated when a train approaches the track switch. The energy thus produced by the transmitting device is transmitted to the loop circuit, or circuits, for the section, or

sections, at the track switch and therefrom transmitted to the train upon which it is received as a signal indicating the position of the track 55 also transmitted to the dispatchers ofiice where it is received as a signal indicating the position of the track switch.

Systems of the above general character are. shown and described in my co-pending applications Serial No. 227,932, filed Oct. 22, 1927; Serial No. 304,483, filed Sept. '7, 1928; and Serial No. 378,000 filed July 13, 1929. The present invention relates to further developments and improvements in such systems.

A principal object of this invention comprehends the provision of a system for indicating on a train, and if desired, on both ends of a train, the position of a track switch as the train approaches said switch.

A further principal object of the invention relates to the operation, in a simple and economical manner, of a track switch so that the train may enter or leave a route connected with the main line without stopping.

Another principal object of the invention is the provision of means for indicating on a train, and, if desired, on both ends of the train, the position of the track switch after the train has passed over the switch.

Another principal object is the producing on the train and in the dispatchers oflice an indication of the position of the track switch, same being made a part of and operated in connection with, a system for communication between the train and the dispatcher.

Another principal object is the provision of means enabling the dispatcher at any time to determine the position of a track switch.

Still another principal object of the invention is the provision of means to instantly warn the dispatcher in case the integrity of a loop circuit for proper operating service is at any time impaired.

To the accomplishment of the foregoing and such other objects as may hereinafter appear, my invention consists in the elements and their relation one to the other, as hereinafter particularly described and sought to be defined in the claims, references being had to the accompanying drawings which show a preferred embodiment of my invention and in which:-

Fig. 1 is a diagrammatic view of a portion of a track district, including a track switch, showing the trackside apparatus and circuits for communication between two trains, between the locomotive and caboose and between one or both of said train points and the dispatcher and for indicating on said train and to the dispatcher the position of the track switch.

Fig. 2 is a diagrammatic view showing the train carried apparatus and circuits for co-operating with the trackside apparatus and "circuits.

Fig. 3 is a view showing a modification of the system illustrated in Fig. 1.

Fig. 4 is a view showing a modified form of train carried apparatus for co-operation with the trackside. apparatusillustrated in Fig. 3.

Fig.- 5 is a partial view of the portion of track illustrated in Fig. 1, and shows apparatus and circuits for operating the track switch.

Fig. 6 shows the construction of a so-called off and on relay, anumber of which are shown schematically in the various figures of drawings under the designations El, E2, E3 and E4.

The system will now be described as one for audible signaling and communication as relates to the transmission and reception of signals on the train and in the dispatchers ofiice.

Identical parts and devices in the various figures are generally marked with the same symbol.

Figures 1, 3 and 5 are fragmentary showings of a stretch of track, such as is comprised in a district controlled by a dispatcher. FI and F2 are the track rails. SW is the track switch leading to another track, as a passing siding ST is a switch stand adapted for operating the track switch by manual power. SM is a mechanism for operating the track switch by electric or other power, as when the operation of the track switch is controlled from a remote point. Contacts l3 and 5 are operated by the movement of the track switch points. I3 is closed when the track switch SW is normal (closed) and open when the switch is reversed (open). 5 is open when the switch SW is closed and closed when the switch SW is open. Si, S2, S3, S4, etc., are sections of track. Intermediate circuits are provided for these sections as hereinafter explained. As here shown, each section is provided with a track circuit of the usual well known character having a battery BY and a relay T. 0 represents electrical insulation in the shafts of the various motor operated devices.

In Fig. 1, M is a motor driving alternating current generators AI and A3, each of a diiferent frequency within the audible range, and commutators or coding devices Cl and C2. B2 is a battery furnishing energy for motor M. Ta and Tb are transformers of a suitable type, each with coils in circuits controlled by the position of the track switch and in inductive relation with a coil in a loop or intermediate circuit.

B is a source of electrical energy and RI a normally energized relay in each intermediate or loop circuit in the stretch of track. B is shunted by a condenser K and RI by a condenser C. .MI and M2 are motors driving ccmmutators or coding devices C3 and C4 respectively. ZI and Z2 are buzzers or rapidly vibrating current make and break devices. El, E2, E3, etc., are relays, sometimes called ofi and on re ays, similar in con str-uction to the-relay E shown in Fig. 6. These relays are each so arranged that when energized the contacts are closed in one position and remain in that position till the relay is again energized when the contacts are shifted to the other position, etc.

Ll, L2, L3, etc., are selectors, each responsive to a certain prescribed code of impulses transmitted into its circuit by. the selective coding device DS in the dispatchers ofiice or wayside sta- .tio'n.

form shown within the boundary line BYI of Fig. 2 and is connected through the transformer Tf withthe dispatchers telephone and selective circuit, including conductors DI and D2. SH is a switch adapted to connect either the transformer Tf or the selective equipment DS in circuit with the conductors DI and D2.

Te is a transformer adapted to connect the intermediate or loop circuits for sections S2 and 83-85 with the conductors DI and D2 which connect with the dispatchers oince or wayside station.

In Fig. 2 is shown the train'carried equipment comprising a transmitter TS, a receiver RC,

switches UI and U2 as one pair and VI and V2 as another pair connected together in one frame SWI to be operated by the movement of the handle H4, an amplifier AMP so arranged as to be used for either receiving or transmitting, a filter FL normally in circuit for receiving, and theinductor Q and the various conductors connecting the devices in circuit. 00 represents a conductor of the intermediate circuit in inductive relation with inductor Q.

Fig. 3 is generally the same as Fig. 1 and differs thereirom chiefly in that the track rails Fl-F2 are a part of the intermediate or loop circuits and that the means for creating indica-' tions for the track switch comprises the well known system of electrical transcription wherein such phrases as Switch SW is closed or Switch SW is open are actually transmitted by the devices A2 and A4 to be annunciated from the re- R.CTS is the same as the detail disclosed within the boundary BYI of Fig. 2, except that inductors Qi and Q2, are connected to the receiver and inductors Q3 and Q4 are forconnection to.

the transmitter. As will be observed the inductors of each pair are connected in series; they may however be connected in multiple circuit.

In Fig. 5 is shown a portion of the same stretch of track as exhibited in Fig. 1. This figure discloses diagrammatically the means for operating the track switch so that trains may enter and leave the siding. MO is the motor for operating the mechanism SM to open and close the track switch SW. RS is alocal relay controlling the operation of the motor MO. E4 lsa relay of the off and on type, heretofore referred to, and is controlled from the dispatchers ofiice, or wayside station, through the operation of the selector L4. The switch operating means shown in Fig. 5 may be used with either the disclosure of Fig. 1 or the disclosure of Fig. 3, and its arrangement is more clearly demonstrated by being shown separately from either of those figures.

In Fig. 6 is shown a typical example of the socalled off and on relay. It will be seen from this figure that the armature A of this relay is provided with a pawl P adapted to engage the ratchet wheel R. which is rigidly attached to the cam CA. Each energization of the relay accordingly advances the ratchet and cam one step. The cam, it will be noted, is so formed that the CK are projections actuate a set of springs on each alternate step. The spring combination shownis similar to that of relay E3 (Figs. 1 and 3), although,

obviously, any spring combination can be used. With the cam in the position shown, the springs disengage their respective back contacts and springs 36 and 40 engage their front contacts. Upon the next energization of the relay, the cam will be advanced one step, thereby permitting the springs to re-engage their back contacts and disengage their front contacts.

In Fig. 1 two complete and two partial loop or intermediate circuits are shown to illustrate the arrangement of such circuits as they would be for a dispatchers district of 100 to-200 miles in length.

The intermediate or loop circuit for section S2 normally comprises, conductor 29, relay RI, conductor 31, back contact 35, conductor 35. front contact 34, conductor 33. transformer coil 32 in inductive relation with transformer coils I6 and 9, conductor 3I battery B and front contact 30. It will be noted that condensers K and C are in parallel with battery B and relay RI respectively, so that communication current impulses of fluctuating current in the circuit may pass through these condensers, because of the smaller impedance in the circuit.

The conductors 29 and 3I are preferably located on the ties in the center of the track so as to be in inductive relation through a small air gap with the inductor Q carried on the train.

The intermediate or loop circuit for the sections S3-S5 normally comprises, conductor 45, transformer coil 44 in inductive relation with transformer coils I4 and 1, conductor 43. front contact 42, conductor 4I. back contact 4|). conductor 39, relay RI, conductor 38. front contact 46 and battery )3 and condenser K in parallel. It will be noted that condensers K and C are in parallel respectively with battery B and relay RI so that communication current impulses may pass through these condensers because of the smaller impedance in the circuit.

The conductors 38 and 45 are also preferab y located on the ties in the center of the track so as to be in inductive relation through a small air gap with the train carried inductor Q.

Transpositions are shown in the two above described intermediate circuits at XP to make two equal loops for each circuit. These transpositions are for the purpose of minimizing the induction there may be from foreign electrical sources. The necessity for, the exact arrangement of, and the number of such transpositions, if any are required, can best be determined from an inspection of conditions on the ground before the installation is made.

The intermediate circuit for section SI and preceding sections and for section S6 and succeeding sections are only herein partially shown. They are of the same general character and arrangement as those herein described in detail for sections S2 and S3S5. To the extent illustrated, conductor 26 is connected through front contact 21 with battery B and conductor 28, condenser K being in parallel with battery B; v and conductor 41 is connected through battery B and front contact 48 with conductor 49, battery B being also paralleled by a condenser K.

Where there is but one track, one side of the intermediate circuit, as a portion of conductors 3I and 29 may be carried on a pole line. Where there are two parallel tracks, both sides of the intermediate or loop circuit may be carried on the two tracks, as is shown for conductors 38 and 45.

The circuit in Fig. 1 for the motor M comprises, electrical source B2, conductor I8, back contact I9 closed, conductor 25 and motor M connected to source B2.' Back contacts 20 and I60 of T3 and TI, respectively, are in multiple with contact I9 being connected to the same conductors. Also, back contacts 22, 23 and I59 of T5, T4, and T6, respectively, and front contact I09 of E4 are adapted to be closed in the same circuit through conductors 2| and 24.

The local indication circuit for the normal or closed position of the switch SW includes generator AI, conductor II, coding commutator CI to give a repetition of successive two dots with a pause between etc.) conductor I2. normally closed contact I3, transformer coil l4, conductor I5, transformer coil I6 and conductor I1.

The local indication circuit for the reverse or open position of the switch SW includes generator A3, conductor 3, coding commutator C2 to give a continuous series of equally spaced dots. etc.) conductor 4, contact when closed, conductor 6, transformer coil 1. conductor 8, transformer coil 9 and conductor I0.

Within the boundaries or frames BY2 and BY3 are disc osed means for giving an indication in the office of the dispatcher or wayside station in case an interruption, as a break or cross, in the intermediate or loop circuit should occur. Since this means as disclosed, is identically the same for all intermediate circuits, except as herein-.

after mentioned. but one such arrangement will be described and that in frame BY2 for the intermediate or loop circuit for section S2. The battery B is located at one end of the circuit and the relay RI at the other end. If there is a break of a conductor," or a cross in the circuit between the battery B and the relay RI, the latter will drop its armature closing the back contacts 62. 5I and 54, resulting int-the clo ing of the circuit including electrical source B3, conductor 50, back contact 5|, conductor 52. motor MI, conductor 53, back contact 54, conductor. 55, front contact 56. and conductor 51, causing coinmutator C3 to be rotated by motor MI to give a code of two short impulses and one long impulse repeated; the closing of the circuit including electrical source B3. conductor 50, back contact 5|, conductors 52 and 10. buzzer'coil of ZI. conductor 69, back contact 68, conductor 61, coil P of transformer Tc, conductor 66, front contact 65 and conductor 51, causing contact 68 to make and break rapidly at a frequency within the audio range; and the closing of circuit including secondary S of transformer T0. conduct r 64, commutator C3, conductor 63, back contact 62, conductor BI front contact 60. conductors 59, 58, DI and I08, transformer Tf. conductor I01, switch SH, and conductors I 04, D2 and 15. The current impulses created by the buzzer ZI and coded by the commutator C3 are induced through the transformer T1 into the circuit of the receiver RC which responds to givean audible signal of the code transmitted, viz., The dispatcher upon hearing the signal may operate his selective equipment DS to cause selector LI to close its contact 12 which energizes-off and on relay EI in a circuit including source of energy B4, conductor 1I, contact 12, conductor 13, relay coil' El and conductor 14. This relay, on being energized, opens its contacts 60, 55 and 65 thus "disconnecting secondary S of transformer T0 from conductor DI and stopping the motor MI and the buzzer ZI.

The dispatcher will then call the,

maintainer to make repairs, and when notified that repairs are made, he will againoperate his selective equipment DS, sending out the prescribed code to which selector LI responds to again energize relay EI to restore the contacts 60, 56 and 65 to their normal condition.

For the intermediate circuit of track section S3-S5 and for other intermediate circuits of the track stretch, the means illustrated in the frame BY3 for indicating to the dispatcher derangement of the intermediate circuit is identical with that explained for intermediate circuit for section S2, except the code of impulses transmitted is different for each intermediate circuit as may also be the frequency of the current impulses. The commutator C4, as illustrated, will code the current as one long and three short impulses repeated" The buzzers ZI, Z2, etc., are each adjusted to different frequencies within the audio limits, which, together with the coding of the signal, will give a sufficient number of indications so that each intermediate circuit in the dispatchers district may have a distinctive indication. This will enable the dispatcher to immediately locate the circuit within which the derangement occurs and promptly arrange for repairs. Instead of using the audible tone and coding system described, I may use the electrical transcription method referred to in Fig. 3 for switch indications, and thus inform the dispatcher in speech the location of the section in which the derangement has occurred.

Relays as Tl, T3, T6, etc.,' at the end limits of intermediate circuits, when de-energized, close their contacts on their back points, thus connecting adjacent intermediate circuits together.

When relay T3 of Fig. 1 is de-energized, the intermediate circuits for sections S2 and S3S4 '85 are connected together, forming one circuit, including conductor 29, relay RI, Icy-passed by condenser C, conductor 31, back contact 36, conductor 35, back contact 34, conductor 43, coil 44 of transformer Tb in inductive relation with coils I4and I of the same transformer, conductor 45, battery B, by-passed by condenser K, front contact 46, conductor 38, relay RI, by-passed by condenser C, conductor 39, back contact 40, conductor 4|, back contact 42, conductor 33, coil 32 of transformer Ta in inductive relation with coils I6 and 9 of the same transformer, conductor 3| battery B, by-passed by condenser K, and front contact 30. This combination of, two intermediate circuits as one circuit is typical of that for the system. When relay TI is de-energized, the intermediate circuit for section SI and preceding sections is connected with the intermediate circuit for section S2 to form one enlarged intermediate or loop circuit, contacts 30 and .21 being made on their back pointsso that conductor 28 is connected through battery B and associated condenser K and back contact 21 with conductor 29; and conductor 3| is connected through battery B and associated condenser K and back contact 30 with conductor 26. When 'relay T6 is de-ener-gized, the intermediate circuits for sections S3S4-S5 and S6 and succeeding sections are connected together to form one enlarged intermediate-circuit. Contacts 48 and 46 being made on their back points, conductor 41 is connected through battery B and associated condenser K and back contact 48 with conductor 38; and conductor 45 is connected through battery B and associated condenser K and back contact 46 with conductor 49.

The circuits and devices illustrated in Fig. 2 are carried on the train. The inductor Q is attached to the train to ride near, and in inductive relation or communications which may be intended for the train. This circuit includes coils and 95, conductors 93 and 94, filter FL, conductor 91,

switch contact U2, conductor- I00, amplifier AMP,

conductor IOI, switch contact V2, conductor I03, receiver RC, conductor I02, switch contact VI, conductor IOI, amplifier AMP, conductor I00, switch contact UI, conductor 96, filter FL and conductor 89. When it is desired to transmit communications from the train the handle I I4 of switch SWI is moved over so that UI and U2 contact conductors 99 and 98 respectively and VI and V2 contact conductors 9| and 92 respectively. It will be observed that only coil is included in the transmitting circuit since it has been found by experiment that a relatively small number of turns on the inductor is more desirable for transmitting while a larger number of turns gives best results for receiving.

The filter FL is adjusted to pass to the amplifier AMP only those frequencies or bands of fre-' quencies desired as useful. In this case of audible frequencies FL will be adjusted to pass those currents of frequencies between about 300 and 2500, which range is practically that used in telephony. v

While I have shown but one amplifier for receiving and transmitting it is evident I may use two amplifiers, one for transmitting and one for receiving, with equally as good results. The amplifiers referred to are usually of the well known vacuum tube type.

Where communication is desired between head end and rear end of train, a set like that illustrated in Fig. 2 is located on both the locomotive and the caboose.

- In Fig. 3 is illustrated how the intermediate or loop circuits may include the track rails, two

complete and two partial intermediate circuits being shown as typical of the arrangement of the intermediate circuits fora dispatchers district.

The intermediate orloop circuit for the sec-- S3--S4-S5 normally comprises, track rails Flv and F2,- condenser CK connecting the track rails to conductor I2'I, front contact 42, conductor I28, back contact 40, conductor I29, transformer coil 44 in inductive relation with transformer coils I4 and 1, conductor I30, front contact 48 and conductor I32 connecting through condensers CK to track rails FI and F2. It will be observed that the track rails of each section are made electrically continuous for communicating currents by the condensers CI around the insulated joints J. The insulated joints between adjoining sections however, are not bridged.

The intermediate circuits for section SI and preceding sections and section S6 and succeeding sections, if completely shown, would be generally the same as described for sections S2 and S3-S4--S5.' For the section SI there is shown conductor I20 connected through front contact 21, conductor I2I and condensers CK with the two track rails FI and F2. For section S6, etc., conductor I34 is connected through front'contact 46, conductor I33 and condensers CK with track rails FI and F2 of the siding. It will be observed for section S2, and partial section SI and preceding sections, that one side of the intermediate circuit is a conductor; as I23 for section S2, carried on the trackway between the track rails, the rails in parallel forming the other side of the intermediate circuit. With such an arrangement of intermediate circuits as disclosed for section S2, either the track rails FI-FZ, or the conductor I23, or both track rails and conductor may be used as the transmitting and re-' ceiving medium co-operating with the train carried equipment. In case the track rails are the transmitting and receiving medium for the train, the train carried equipment would be like that illustrated in Fig. 4. If the conductor is the transmitting and receiving medium, the train carried equipment would be like that shown in Fig. 2. In case both the track rails and the conductor are used to co-operate with the train equipment, the inductor arrangement would need to be a combination of the inductors of Figs. 2 and 4,01 3, modification thereof, so that the pickup and transmitting coils of the inductors would be aiding in their cooperation with the rails and the conductor for receiving and transmitting.

In installations on any railway district the system may include the two types of intermediate circuits, that of Fig. 1 and that of Fig. 3. Ordinarily, though not necessarily, one side of the intermediate circuit, of the type disclosed in Fig. 1, is carried on the pole line and the other on the track. It is apparent that where a pole line is not available, the type of intermediate circuit shown for section S2 of Fig. 3 may be used to advantage. In the case both types of intermediate circuits are used, one for some track sections and the other for other track sections and the conductor on the track is the transmitting and receiving medium, the train equipment of Fig. 2 will perform satisfactorily with either. Also, I may choose to use the train carried system with inductors co-operative with an arrangement of intermediate circuits having either the track rails or the conductor on the track as the transmitting and receiving medium. It will be noted that in the intermediate circuit of section S3S5, the track rails of the siding are inparallel circuit with the track rails of the main line.

Assuming the stretch of track illustrated in Fig. 1 is to have for section S2 an intermediate or loop circuit which includes the track rails like that shown for section S2 in Fig. 3, the conductor I23 being located in the center of the track would be in co-operation the same as conductors 38 and 45 of Fig. 1 with the train carried inductor Q. Also, for the interval the train is in section S3, conductor 43 would be connected through back contact 34, conductor 35' and back contact 36 with conductor I24 (Fig. 3) and the track rails FI and F2 of section S2 (Fig. 3) would be connected through condensers CK, conductor I26, back contact 42, conductor 4| (Fig. 1) and back contact 40 with conductor 39. In this latter connection, since conductor I26 takes the place of conductor 33 there would also be a path through back contact II2 connecting conductor I26 with conductor 39. With such a combination of intermediate or loop circuits, it is evident dispatcher may operate the relay E3 to connect the dispatchers circuit conductors DI through the transformer Te with the loop circuits for sections S2'and S3S4S5, orfor said two 1 loop circuits. combined.

The circuit for the motor M as shown in Fig. 3 is the same as that heretofore described for Fig. 1, excepting I have not shown in this figure control of motor M by the dispatcher controlled relay E4. However, the manner of effecting such an arrangement is evident.

In Fig. 3 the local indication circuit for the normal or closed position of the switch SW includes transmitting device A4, conductor I5'I, contact I3 closed, transformer coil I4, conductor I5, transformer coil I6 and conduuctor I58. The local indication circuit for the reverse or open position of the switch SW includes transmitting device A2, conductor I55, contact 5 when closed, transformer coil I, conductor 8, transformer coil 9 and conductor I56.-

I have not shown in this Fig. 3 means for indicating the integrity of the intermediate circuits,

but it is evident I may use such means. The bat-.

tery B with its parallel condenser K and the circuits and equipment in frames BYZ and BY3 illustrated in Fig. 1, may be inserted within the conductors I23 and I30 of the intermediate circu'its respectively for sections S2 and S3-S5, and

a distinctive signal may be produced for each intermediate circuit.

Instead of the devices shown in Figs. 1 and 3 for supplying energy for the switch indications, I may use other means, such as a vibrating relay of a type similar to ZI and Z2 of Fig. 1. The latter means would be satisfactory in many situations where signal means receivable on a train is required for a limited number of track switches.

Also, I may use other means than those explained for indicating to the dispatcher the decircuit, any current impulses in the track rails FI and F2 at any instant will be in the same di-.

rection and therefore, induced into the inductors QI and Q2 in the same direction. As the coils of the inductors QI and Q2 are connected in aiding the induced current as a maximum will pass through the filter FL and the amplifier AMP to the receiver RC. A so, as the coils of the inductors Q3 and Q4 are connected in aiding, current impulses transmitted from the trans mitter TS will be induced into the track rails to have the same direction at any instant.

In Fig. 5 the circuits are shown in their normal condition. The conductors DI and D2 are the same as shown in Fig. 1, connecting with the wayside station .or dispatchers oflice. Selector L4 is operated to close'its contact when selective equiment DS (Fig. 1) is operated in a circuit including switch SH closed on conductor I05, conductors I04 and D2, selector L4 and conductors DI, I08 and-I05. With contact I54 closed, relay E4, which is of the oil and on. type. is energized in a circuit comprising, battery B8, conductor I52, coil of relay E4, conductor I53 and contact I54. Thus, contacts IIO and-III are closed. When back contact I38 is closed, relay RS is energized in a circuit comprising battery 31, front contact IIO,,conductor I43, coil of relay RS, conductor I42, contact I38 closed when there is a train in section S2, and conductor I39. Contact I40 is connected to battery B1 and by conductor MI in the circuit forrelay RS in parallel with contact I38. With contact I48 closed on its front point and contact III closed, motor MO is caused to operate mechanism SM to open the track switch, the circuit being battery B6, conductor I45, contact I44, conductor I49, front contact I48, conductor I50, contact III closed, conductor I5I, motor MO and conductor I40. When contacts I38 and I40 are open, after either or both have been closed energizing relay RS, relay RS is de-energized, closing its back contact I48 and the track switch SW is closed, the motor MO operating the mechanism SM being in the circuit including the battery B6, conductor I45, contact I44, conductor I49, back contact I48, conductor I lI, motor MO and conductor I46. In power mechanisms for switch operation the arrangement is usually such that, when the track switch is operated to a desired position, the motor ate the track switch to the other of its two positions whenever the outside circuit controllin devices are operated to correspond. It is such an arrangement I propose to use in connection with the. circuits and devices controlling the operation of the track switch in this invention.

Operation of the system I will first describe the operation as a communicating system, assuming that communication is by telephone and that audio frequencies are used.

Assume a train equipped for communication on both the head end and rear end as-indicated in Fig. 2, that the train is wholly within'the section S2 of Fig. l 'and telephone conversation is being carried on between the train conductor in the caboose and the engineman at the head end'of the train. The inductor Q for each set on each end of the train is in inductive relation with either the conductor 29 or 3I or with both of them, depending upon the location of the train in the section. The train conductor in the caboose operates switch SWI to connect the transmitter TS through the amplifier with the coil 95 of the inductor Q. He then proceeds to talk-into the transmitter, creating current impulses, corresponding to the conversation, in the inductor Q which impulses are induced into the intermediate circuit through the conductor 29 or 3|. These impulses are carried through the intermediate circuit, heretofore described, to the inductor Q on the head end of the train, at which point they are induced into said inductor to flow through the coils 90 and 95, the filter, the amplifier and the circuit of the receiver RC, which responds to reproduce for 'the engineman the speech transmitted by the train conductor. 7 talking the train conductor operates his switch SWI to place the circuits and receiver of the caboose set in normal condition. The engineman may now. reply, the operation in doing so being similar to that described for the conductor talk- Assume the train advances into the section S3 in which case the relay T3 is de-energized to 'When through open the front contacts 42, I44 and 34 and close the back contacts 20, 42, 34 and H2. The intermediate circuits for the two sections of track, that is, for S2 and S3S4S5 are now connected together as one loop circuit as already herein described. It will be noted that the conversation between the engineman and train conductor may be continued without interruption through this temporarily enlarged intermediate or loop circuit.

Assume the train has continued on to the siding so as to be wholly within the section S5.

Since the train has cleared the track circuit of section S3, relay T3 has become energized, re-

cuit having already been described.

During the interval that the train was in the track section for relay. T3, conductor 38 was connected by way of conductor 39, back'contact 40 and back contact 42 with conductor 33, transformer coil 32 and conductor 3I, etc.; also, conductor 29, was connected by way of conductor 3'1, back contact 36 and back contact 34 with conductor 43, transformer coil 44, conductor 45, etc. It will be noted, therefore, that the conductors of the two intermediate circuits were connected in transposed relationship. Since each of these intermediate circuits is electrically separated from the adjacent intermediate circuits, the train is continuously in a communication zone comprising first one intermediate or loop circuit, then two intermediate circuits connected together, then one intermediate circuit, etc. This is considered as a communication zone traveling with the train to which communications for and from the train are confined. For convenience, this arrangement is referred to as a traveling intermediate circuit or zone;

While the trainwas in section S2, or traveling in section S3, or while in section S5, the dispatcher may have communicated with it had he so desired after operating the selector L3. To operate the selector L3, the dispatcher shifts the switch SH to connect with conductor I05, thus connecting the selective equipment DS with the conductors DI and D2. He then operates the appropriate selector key, sending out the code of current impulses to which .selector L3, and none other, responds. These impulses flow by Way of conduct tors DI and D2 and 82 and 83. When selector L3 is operated, contact I8 is closed in the circuit for relay E3, comprising battery B5, conductor 80, coil of E3, conductor I9, contact I8 and conductor 8I. With this energization of relay E3, the contacts 40, '36 and 86 are closed on their front points as heretofore explained, so that secondary SB of transformer Te is 'now in the intermediate circuit for section S2 and the secondary SA is connected in the intermediate circuit for the section S3S4S5. The closing of contact 86 connects the primary P of transformer Te with the conductors DI and D2. The dispatcher now returns the switch SH to its normal position, connecting conductors I04 and I01. He now operates his telephone equipment, which has been heretofore referred to as being identical with that included in the frame BYI, talking into his transmitter TS so that the current impulses corresponding to the speech transmitted, pass through the amplifier AMP and over the conductors 9| and 93, through the transformer Tf, conductors DI and D2, 82 and 83, 85 and 88 and contact 86 to the primary P of transformer Te where they are induced into the secondaries SA and SB for the two intermediate circuits. If the train is in the intermediate or loop circuit for section $2, the current impulses induced into the secondary SB of the transformer Te are carried through the intermediate circuit, with which the inductors Q of the train are in inductive relation, and through these inductors, the amplifiers and connected circuits to the receivers RC where they are reproduced on both ends of the train as the conversation transmitted by the dispatcher. .Should the train have moved from section S2 to $3, the two intermediate circuits, that for section S2 and that for section S3S4-S5 are connected together as heretofore explained. Hence, the communication between the dispatcher and the train may be continued. During the interval that the train is in section S3, back contact H2 is closed, shunting the secondary SA, so that only the secondary SB is available for transmitting the communication currents between the dispatchers line DI and D2 and the intermediate circuits. The object of the shunting of the secondary SA is merelythat of reducing the impedance of the enlarged intermediate circuit. While the train is in the section S5, the communication between the dispatcher and the train will be by way of the secondary SA of transformer Te. The train conductor or the engineman, or each of them alternately, may reply to the dispatcher in conversation while the train is in any of the track sections, the procedure in operation by either the engineman or the train conductor being the same as heretofore described when they are carrying on conversation between themselves. The current impulses induced into the intermediate circuit passthrough the transformer Te to the dispatchers wayside telephone line, including conductors DI and D2, and thence by way of transformer Tf, the filter FL, the amplifier AMP and circuits to the receiver RC in the dispatchers office where the receiver RC reproduces the conversation transmitted by the train conductor and engin'eman. The current impulses from the train to the dispatcher, pass through the secondary SB of transformer Te while the train is in sections S2 and S3 and through the secondary SA while the train occupies either the section S4 or S5. Since the connection of transformer Te is selectively controlled, as are the similar transformers for other sections in the district, it is evident the dispatcher may connect his telephone circuit, including conductors DI and D2, with the intermediate circuits of other sections in the district for conversation with trains in those sections, such conversation being carried on privately with a train where such train is the only one within the section or sections for inter-- mediate circuits controlled by one selector. Where it is desirable, the dispatcher may talk at one time with several trains in different parts of the district by operating the selectors, corresponding to the location of the trains to connect the transformers for the respective intermediate circuits to his telephone line, conductors DI and D2; and the attendants on each of these trains may reply to the dispatcher, the attendants on other of said trains hearing the reply. As is further evident, a transformer with one primary and one secondary may be used to connect the conductors DI and D2 with but oneintermediate circuit at a time if desired.

If there are two trains in a section, or sections.

having one intermediate circuit, conversation may be carried on between the trains in a manner similar to that when conversation is carried on between the two ends of a train. Also, by operating the appropriate selectors connecting the intermediate circuits for two or more remote sections to the conductors DI and D2, trains in those sections may carry on conversation with each other, the operation in talking being similar to that when the train conductor and the engineman of the same train talk with each other.

The procedure in communication with the wayside arrangement of Fig. 3 is practically identical with thatdescribed for Fig. 1. Where the center ,of track conductor is the co-operating medium for communication, the train carried system indicated in Fig. 2 is used. If the track rails are the co-operating medium for communication, the train carried system illustrated in Fig. 4 is used.

I shall now describe the operation of the track switch SW with particular reference to Fig. '5. This switch may be operated manually by the hand throw stand ST or by the mechanism SM and the motor MO. Many railway switches are now in service equipped with both means for operation, the hand throw stand ST being provided for use in emergencies, as when the power mechanism operating means is out of order.

The stand ST usually has two levers, I to con-' I operate the track switch by both the man-- ual and power means, the manual means being as heretofore described. The power control means is a novel arrangement requiring the cooperation of the dispatcher with the train in order that the switch may operate. Because of the communication system provided, and herein described, communication between the dis-- patcher and trains may be frequent, and whenever desired by the dispatcher. For this reason the dispatcher may be always informed as to the necessity for a train to enter and leave a passing siding and may so inform the train attendants.

Assume that a train is. proceeding in the direction indicated by the arrow and is required to enter the siding. The dispatcher, from the selective equipment in his oflice, sends the proper code of electrical impulses over the circuit, conductors DI and D2, tozoperate selector L4 which responds to close contact I54. With contact I54 closed, relay E4 operates to close contacts III) and III in" the circuits respectively for the relay RS and the reverse operation of the motor MO. When the train enters section S2 relay T2 drops its armature, closing contact I38 and the circuits are completed, as heretofore described, for relay RS to energize and close the contact I48 on its front point and motor M0 to respond and operate mechanism SM to open the track switch SW. Relay RS is energized while the train is in section S2 and section S5. While the trainis in section S3, relay T3 opens and holds open contact I in the motor circuit so that motor MO cannot operate to cause the switch SW to move under the train. After the train has entered the siding and cleared the section S5, relay RS becomes de-energized and contact I48 closes on its back point completing the circuit for motor M to operate the mechanism SM and close the track switch.

Assume that a train on the siding desiresto come out on the main line. The dispatcher is informed of such movement through the communication system and closes the contacts III] and III. As soon as the train enters section S contact I40 closes, energizing relay RS so that motor MO operates to open the track switch SW. The sequence and features of operation are now similar as above described in detail for. a train entering the passing siding. .When'the train leaving the siding has passed over the track switch SW and cleared the section S2, relay'RS This- SW is non-operative.

" I will now describe the arrangement shown in Fig. 1 which provides indications as to the position of the track switch receivable upon the train and in the wayside station or dispatchers oifice.

As the contacts I3 and 5, are adapted to be controlled by the position'of the track switch SW, whether the switch is manual or power operated, the indications of the position of the track switch'about to be described are received upon the train in either case; and not only is the position of the track switch known to the engineman as the train approaches and passes over the track switch, but the reception of these indications in'the caboose of the train enables the conductor of'the train to check the return of the track switch to its normal position after the train has passed over the track switch in entering and leaving passing sidings. Also, where the track switch is to operate on the approach of a train, with the arrangement of circuits heretofore described, the engineman will get an indication of the position of the track switch before and after the'operation of the switch, which information is *ofvalue in the control of the train., The dispatcher, as he desires, may receive an. indication 'ofthe position of the track switch whether a train is in the vicinity or not.

Normally, the switch SW is set for the main lineand'all the, circuits having to do with switch indications are heretofore explained. Assuming airifinovingoverthe main track in the direcion of the arrow and arriving in the section SI,

theback COIitaIi I60 controlled by may TI is closed in thecircuit of motor M so that motor operates driving generators AI and A3 and the respective commutators CI and'C2. The contact I3, controlled by the switch SW isclosed because the switch is closed. Alternating'current' generated in Al is coded by the commutator CI as and flows through the transformer coils I4 and I6 from which it is induced into the respective corresponding coils 44 and 32 in the intermediate or 100p circuits for sections S3-S4--S5 and S2 respectively. Since the train is in section SI, relay contacts 30 and 21 are closed on their back points so that the intermediate circuits for section SI and preceding sections and section S2 are connectedtogether as one .circuit, as heretofore described. "Therefore the above coded current induced into the coil 32 flows in this temporarily enlarged intermediate or loop circuit for the several sections-as explained. As the train is equipped for communication purposes on both ends thereof with the devices and circuits of Fig, 2, the current impulses in the intermediate circuit referred to are induced from the conductor 26 into the inductors Q and carried to the receiver RC on each end of the train where they are reproduced as an audible signal, corresponding to the transmitted current impulses, indicating the switch SW to be in the normal position. While the train is inthe sections S2, S3 and S4, the corresponding relays T2, T3 and T4 are tie-energized, closing the respective contacts I9, 20 and 23 in thecircuit for motor M so that the generating of the current impulses continues and the indications received upon the train are maintained through the cooperative relationship of the train carried inductors with the several intermediate circuits for the sections passed through by the train. It will be noted that the de-energi zation of the relays T3 and T4 effects a combination of adjacent intermediate circuits as heretofore explained. On

some railroads the reception on the train of the indication of the track switch SW, after the train has passed over the switch, may be objected to as unnecessary, For the above assumed train, the reception of the indication may be cut off when the train clears the section S3; and for single track roads a system of directional relays may be provided to discontinue the indication as noted, but the system will be, effective to indicate the position of the switch for trains bound in the opposite direction from that just mentioned, as will now be described.

Assuming a train running on the main line approaching the closed switch SW in the direction opposite to that indicated by the-arrow, when it arrives in section S4, relay T4 is de-energizedclosing back contact 23, starting the motor M and the generation of current by the generator AI. This coded generated alternating current is induced into coils 32 and 44 of transformers Ta and Tb respectively. Since coil 44 .is in thewintermediate' or loop circuit for sections S3 S4S5, the current impulses in the conduc tors 38 and 45 ofjthat circuit are induced into the inductorsxQ on the train and-carried to the receivers RC where they are reproduced as audible signals indicating the switch to be in its nor,-

inal or closed position. When the train entered the section S4, relayT4 de-energized relay T6 to close contacts 48 and 46 on their back points,

thus connecting the intermediate circuit for the sections S3S4-S5 with the intermediatecircuit, only partially shown; including conductors 41 and to the right of the Fig. 1, as heretofore Therefore, the coded current 1m explained. pulses designating the normal position of the switch SW, as induced into the coil 44, flow in the combined or enlarged'intermediate circuit and are received on the train caboose as well as the locomotive, the inductor Q of which is in inductive relation with conductor 49. When the train arrives in section S3. relay T3 is de-energized, closing contact 20, to continue the operation of motor M; and contacts 42 and 34 on their back -andIII.

inductors Q on the train and carried throughpoints connect intermediate circuits for sections 82 and 83-84-85 together. The transformer coils 44 and 32 are now in series in the enlarged intermediate circuit; and, because of the inductors Q on the train being in inductive relation with the conductors 45 and 38, the indication on the train of the normal position of the switch. continues. When the train has cleared the' section 84, the combination of the intermediate circuit for sections 83-84-85 with that including the conductors 41 and 49 is discontinued. As the train continues into section 82, the intermediate circuit for section 83-84-85 is disconnected from that for section 82 and the contact I9 closes maintaining the motor M and connected plant in operation to induce the indicating impulses into coil 32, now in the intermediate circuit for section 82. The inductors Q receive the current impulses from the conductors 3I and '29 and the indication of the normal position of, the switch is continued on the train. When the train arrives in section SI relay TI isde-energized opening front contacts 30 and 21 and closing'back contacts 30, 21 and I80, thus continuing the operation of motor M and connected plant and connecting together the intermediate circuits for.

section 82 and SI, and associated sections not illustrated. The inductors Q on the train come into inductive relation with the conductor 26 and the normal or closed indication for switch SW persists on the train till the train passes out of section SI and relay TI is again energized.

Assume the train is in section SI traveling in the direction of the arrow and the dispatcher desires it to pass into the siding. He first operates the selector L3 energizing relay E3 to change its contacts so that coil P of transformer To is connected to the dlspatchers communication circuit conductors DI and D2 and secondary SB of the same transformer is connected in the intermediate circuit for section 82. Since the train is in section SI the intermediate circuits for section SI and associated sections, not shown, are connected with the intermediate circuit for the section 82. The dispatcher communicates his instructions to the train that it shall take the siding. He then operates the selector L4 (Fig. 5) to cause the relay E4 to close the contacts IIll As the train is in the section SI, back contact I is closed in the circuit causing motor M and its connected plant to operate such that generator AI induces coded alternating current into coil 32 of transformer Ta. This current flows inthe combined intermediate circuits for sections SI and S2 and is induced from conductor 26 to the inductor Q on the train indicating to the train that the track switch SW is in its normal position. As the train proceeds into the section 82, relay T2 closes its back contact I38, see Fig. 5, in the circuit of relay RS, energizing this relay to close contact I48 on its front point. The closing of contact I48 on its front point completes the circuit for motor MO causing it to operate mechanism SM to open the track switch 8W. As soon as the track switch is operated, contact I3 is opened, and as soon as the switch is open, contact 5 is closed in the circuit f generator A3 and coding device C2. Therefore, current is induced from coils I and 9 into the coils 44 and 32 respectively. Since coil 32 is in the intermediate circuit for section 82, the cu rent flowing in this intermediate circuit, as well as in the enlarged intermediate circuit including the section SI while any part of the train is in section SI, is induced intothe the amplifier and circuits connecting the inductors with the receiver RC. Thisreceiver transforms the alternating current impulses into an audible signal indicating the open position of the switch. This is heard on.the train by both the engineman and the conductor. Accordingly, the train proceeds, the attendants knowing the switch is properly set for the train to enter the siding. As'the train proceeds entirely into section 82 relay TI is energized and the intermediate circuit is now only that for section 82. In the meantime, as the dispatchers wayside station is connected through conductors DI and D2 and transformer Te withthe intermediate circuit for section 82, the dispatcher has also re-. ceived the indication in his ofiice that the track switch SW is now in the open position. With the train in sections 82, S3 and 85, contacts I9, 28 and 22 respectively are closed on their back points so that the motor'M and its connected plant is continued in operation and the indication of the position of the switch is continued to be received on the train. While the train is in the section 83, relay T3 is de-ener gized, see Fig. 5, opening contact I44 in the circuit of motor M0, the arrangement being such that the switch 8W cannot be operated under the train. When the train is in section 85, back contact I40 is closed in the circuit of relay RS, energizing said relay that contact I48 is closed on its front point. When the train clearsthe section 85, relay T5 is energized, opening the back contact I 48 so that relay RS becomes-de energized closing contact I48 on its back point and causing motor M0 to operate the mechanism SM to close the track switch SW. In this movement of the switch, contact 5 is opened and contact I3 is again closed. When the train gets into the section 88, contact I59 is closed, con- .tinuing the operation of the motor M and itsv connected plant. But since contact 5 is now open andcontact I3 is closed, current from the generator AI is induced from the coil I4 into the coil 44; and as coil 44 is in the intermediate circuit for sections 83 and 85, the current impulses flow in this intermediate circuit. The deenergization of relay T6 closes the back contacts 48, 48 and I59. The first two of these connect together the intermediate circuits for sections 83-85 and section 86, and associated sections not shown. The contact I 59 continues in operation the motor MO and. the associated plant with the result that as soon as the switch completes its movement to the closed position, an indica- 85, the relay T6 is de-energized, opening its front contacts 48 and 46 and closing its back contacts 48, 48 and I59. The closing of back contacts 48 and 48 connects together the intermediate circuits for sections 83-85 and S6. The closing of back contact I59 operates 'the'motor M and the associated plant. As the track switch SW is assumed to be normal, an indication of that fact is received upon the train by way of transformer coil 44 in the intermediate circuit for sections S3S5 and section S6, etc. In the meantime, the dispatcher has ascertained in the usual manner by communicating with the train that it is on the siding and is ready to leave. structs it to leave and immediately operates the selector L4 to energize the relay E4 to close the -contacts H0 and lil, these contacts being normally left open. As the train proceeds into section S5, it closes the contact I40, energizing the relay RS to close its front contact I48 in the circuit'of the motor M0 to operate the mechanism SM to open the switch SW. As a result of this operation, contact I3 is opened and contact 5 is closed. Therefore, the train inductively receives from the intermediate circuit through its inductor Q the current impulses which are transmitted to the receiver RC indicating that the switch is open and, it is proper for the train to proceed. The train proceeds with the various sequences of operation and the indication of the position of the switch being maintained in a manner similar to that which has heretofore been explained. As soon as the train clears the sec- 'tion S2, contact I38 is opened and. the switch automatically returns to the normal or closed position. While the train is in the section SI, the relay Tl being de-energized closing back contacts I60, 30 and 21, the motor M andits associated ,plant is continued in-operation and the two intermediate circuits, that for section SI and associated sections and that for section S2 are connected together. Therefore, the current impulses are transmitted by the generator Al through the transformer Ta into the two now combined intermediate circuits with the result that the inductor Q, being in co-op'eratlve relation with conductor 26 there is received on the train the indi- .cation that the track switch SW has returned to its normal position. When the train has proceeded to clear the section SI, contact I80 opens and motor M stops and no further indication is received on the train. During the time that the train was proceeding out of the siding. through the sections S3 and S2 and into the section SI, the dispatcher has permitted the connection of the intermediate circuits for sections 82 and S3S4S5 to remain with his wayside telephone line conductors-DI and D2. He therefore, has received the indications of the position of the switch in a manner similar to that received on the train. After the switch has been restored to its normal or closed condition he may then operate the selector L4 to open the contacts H0 and I'll, making it impossible for the switch to be again operated by a train until he is ready for such operation. I

In Fig. 1 I show a relay E4, controlling front contacts I09, H0 and Ill. The same relay, with its circuits and means for control by selector L4 is illustrated in Fig. 5 and heretofore explained. This relay, when operated to "close its contact Hi0, closes the circuit for motor M, causing this motor to drive the generators Al and A3, each with its associated commutator Cl and C2 respectively. This results in signaling current corresponding with the position of the track switch SW being induced in the intermediate circuits for sections S2 and S31S4S5 through transformers Ta and Th respectively. After having operated selector L4, the dispatcher may operate selector L3 to close the contacts 36 and 40 on their front points,

k thus connecting his wayside telephone circuit conductors DI and D2 through the transformer Tewith the intermediate circuits above referred to. With the switch SH closed, the signaling current He therefore, in-

impulses induced into the intermediate circuits S2 and 83-84-85 pass by way of transformer Te, the conductors DI and D2 and I08 and I01, the transformer T1 and conductors 89 and 93 to the receiver R0 of the set RCTC'in the dispatchers office, where they are reproduced as a signal indicating the position of the track switch SW. When there is no train in the vicinity of switch SW or one is expected, it is often of advantage to the dispatcher to be able to quickly ascertain the position of a track switch, as SW, leading to a passing siding or a branch line. Further, under some conditions it may be desirable for the dispatcher-to control the production of the track switch indication rather than that the control be automatic by the approach and passing of trains. In this latter case, as is obvious, circuit closing contacts 50, I9, 20, 22, 23 and'l59 are not necessary. It may also be desirable, in some cases, to meet the requirements of the railroad, to operate the contact I09 from another relay similar to E4 controlled by another selector similar to L4. There would then be the difference that the dispatcher could set the means in operation to produce the switch indication and he could operate the means for controlling the operation of the track switch, each independently of the other, the arrangement-for such a separation of functions being readily evident.

The operation with the system shown in Fig. 3 of the switch SW, either manually or by power, and the means for producing, transmitting and receiving the indication of the position of the switch on the train and in the dispatchers oiflce is substantially the same as that which has been described above for Fig. 1. The transmitting means A4 and A2 cause electric currents to flow in .the respective circuits for the closed and open positions of the switch SW of such character that,

means for informing the dispatcher of interruption to the proper functioning of the intermediate circuits. The relays RI should be of the slow release" type so that the contacts 62, SI and will not close until an appreciable time has elapsed after the derangement of the circuit occurs. This will guard against any possible operation of a relay RI when contacts, such as 36 and 40 are shifted from one point to the other.

The volume and quality of the switch position signals, as received upon the train and in the dis-' patcher's ofllce, may be such as to be easily distinguishable and yet not appreciably objectionable in the receipt of voice communications transmitted simultaneously with the switch signals. The same features of arrangement and adjustment may be applied, if desired, in connectionwith receiving in the dispatchers office the "out of order" signals for the intermediate circuits.

While I have designated the system of communication and switch indication in this disclosure specifically as an audible system, it should be understood that the same general method may be used for other forms of communication and indications. For example, I may use a carrier current for the voice transmission between the ends of trains and between'trains and dispatcher and either audible or visual means on some other said-local circuit active when'said switch is in frequency for the switch indications and for the out of order signal for the intermediate circuits. Where I use. carrier current for communication between train stations and between trains and the dispatcher and audible frequencies for switch indications and for the intermediate circuit out of order signal, the train and dispatchers station equipment will be on the order of the disclosure in my patent application Serial No. 306,905, filed September 19, 1928, Figs. 1 and 2.

What I claim as new is:'

1. In a train operating system, a stretch 01' track for a train, a track switch in said stretch, means for operating said switch to either of two positions, a loop circuit in said stretch, two 8811- erating devices forproducing coded impulses oi electric current, train controlled means for simultaneously starting both of said devices responsive to a train approaching said stretch of track, switching contacts controlled by each position of said switch for connecting said devices individually to said circuit, and receiver means on said train in electrical relation with said loop circuit responsive to said coded current impulses to indicate either position of said switch.

2. In a train operating system, a stretch of track for a train,a track switch in said stretch, intermediate circuitsin said stretch, one or said circuits being in the section of track approaching said track switch, means governed by said train, as it approaches said track switch, and controlled by the position of said switch, for transmitting electric current into said one circuit, and means associated with said circuits adapted to electrically connect adjacent circuits so that the electric current in said one circuit may flow also in the loop circuits adjacent the said one circuit.

3. In a trainoperating' system, a stretch of track for a train, a track switch in said stretch, intermediate circuits in said stretch, at least one of said circuits being in the section of track approaching said track switch, a current generating device, means governed by said train, as it approaches said track switch, and controlled by the position of said switch, for connecting said current generating device into said circuits, and receiver means on said train in inductive relation with-said circuits and responsive to the current in said circuits.

4. In a train operating system, a stretch of track for a train, a track switch in said stretch, a closed metallic loop circuit in said stretch, electric current in said circuit controlled by the position of said track switch, a wayside station, and receiver means on said train and in said wayside station in electrical association with said loop said wayside station in electrical relation with said circuit and responsive to said current to lndicate each position of said switch by a distinctive signal.

6. In a. train operating system, a stretch of track for a train, a loop circuit in said stretch, a track switch in said stretch, a local circuit in inductive relation with said loop circuit and controlled by the position of said switch,- means in one position to induce a signal current in said loop circuit, a train on said track, a wayside sta tion, and receiver means on said train and in said wayside station in inductive relation with said loop circuit and responsive to said signal current.

7. In a train operating system, a stretch of track for a train, a train on said track, a track switch in said'stretch, intermediate circuits in said stretch, one of said circuits being in the section of track approaching said track switch,

means governed by said train and controlled by the position of said track switch for causing electric current to flow in said one loop circuit, means associatedwith said circuits adapted to electrically connect adjacent circuits so that the electric current in said one circuit may flow also in the circuit of the circuits adjacent the said one circuit, a wayside station, and receiver means on said train and in said wayside station adapted ior electrical relationship withand responsive to the electric current in said circuits.

8. In a train operating system, a stretch of track for a train, track switches in said stretch,

.intermediate circuits in said stretch associated active when said switches are in either of theirv two positions, a wayside station, a circuit extending from the stretch of track to said station, and a receiver in said wayside station adapted to be selectively connected via said last circuit with any one of said intermediate circuits and responsive to current therein -to indicate the position ohthe associated switch.

9. In a train operating system, a stretch of track for a train, a track switch in said stretch, an intermediate circuit in said stretch, electric current in said circuitactive when said switch is in either of its two positions and only when said train is approaching said switch, a wayside station, a circuit extending from the stretch of track to said station, and a receiver in said .wayside station in electrical relation with said intermediate circuit via said last circuit and responsive to said current.

10.'In a system for operating trains, a stretch of track for a train, a track' switch in said stretch, a wayside station, a wayside circuit including the rails of said stretch of track, means controlled by said switch in its open and closed positions, and also selectively controlled from said wayside station, for causing electric currents harmonizing with the open and closed positions of said switch to flow in said wayside circuit, and receiver means in said wayside station adapted to be connected with said wayside circuit and responsive to said electric currents, the arrangement being such that the dispatcher in a wayside station remote from said switch may determine whether said switch is in its open or closed position.

11. In a train operating system, a stretch of track for a train, a track switch in said stretch, a wayside station, mechanism for operating said switch, means co-operatively controlled by said train and said wayside station for operating said mechanism, a wayside circuit in said stretch, electric current in said wayside circuit controlled by the position of said switch, and receiver means on said train and in said wayside station operatively associated with said wayside circuit and I responsive to said current to indicate the position of said switch.

12. In a train operating system, a stretch of track for a train, a wayside station, a circuit for said stretch, a track switch in said stretch, electric current in said circuit controlled by the of track occupied by trains, a wayside station,

Wayside circuits in said stretch, each adapted to transmit fluctuating electric signal currents between said trains and said wayside station, and means in each of said circuits co-operating with means in said wayside station adapted to give a distinctive alarm in said wayside station for each of said circuits when a circuit becomes inoperative.

14. In a train operating system, a stretch of track for a train, a track switch in said stretch, a wayside station, means controlled by the approach of the train to said switch in co-operation with means controlled from said wayside station to open said switch, means controlled by said train operative after the train has passed over the switch to close said switch, a circuit in said stretch, electriccurrent in said circuit controlled by both the open and closed positions of said switch, and receiver means on said train and in said wayside station in inductive relation with said circuit and responsive to said current.

15. In a train operating system, a stretch of track for a train, a track switchin said stretch, a wayside circuit in said stretch, a normally inactive source of electric current, means controlled by said switch for connecting saidcurrent source to said wayside circuit, means controlled by said train for rendering said source active to deliver current to said wayside circuits, and receiver 'means on said train in electrical relation with wayside station, and a circuitincluding a re-',

ceiver carried on said train in electrical relation with said intermediate circuit, said receivers being responsive to said currents.

1'7. In a train operating system, a stretch of track containing a train, a track switch in said stretch adapted to be operated to either the open or closed position, an intermediate circuit for said stretch, means causing an electric cur,- rent to flow in said intermediate circuit corresponding to each the open and closed position of said track switch, a circuit carried on said train in electrical relation with said intermediate circuit, and a receiver in said train carried circuit responsive to the electric current in said intermediate circuit to indicate the position or said track switch when saidtrain is approaching said track switchand after the train has passed over.

the track switch.

18. In a railway operating system, a main line of railway with a train moving thereover, a track switch therein connecting with a siding, a wayside station, transmitting and receiving telephone sets on said train and in said wayside station, an intermediate circuit for said main line of railway and said siding of which the running ing said track switch to its opened and closed I positions, means controlled by the position of said track switch causing electric currents with characteristicswhich are distinctive for each position of said track switch to flow in said intermediate circuit, and devices controlled fromthe wayside station over said wayside circuit, connecting the intermediate circuit with the wayside circuit and, in co-operation with the approach of the train to the track switch, controlling the operation of said mechanism. I

19. In a train operating'system, a stretch of railroad track, a train on said track, a track switch in said stretch of track, means for operating the switch to either of two positions, a wayside circuit associated with said stretch of track, a normally inactive currentgenerator, circuits controlled by said train for rendering said generator active, and circuits operative in accordance with the position of said switch for,

connecting said generator to said wayside circuit.

20. In a train operating system, a stretch of railroad track, a closed electrical circuit associated with the stretch of track and adapted to co-operate with transmitting and receiving apparatus carried by trains operating over the stretch of track for conveying signals between the same, a wayside station, a line extending from said station to said circuit, said line being normally disconnected from the circuit and adapted to be connected therewith for conveying signals between 'the apparatus and the station, and signaling apparatus associated with said circuit efiective, response to the circuit becoming inoperative, to convey said signals, for transmitting a distinctive signal over said line to the wayside station.

21. In a train operating system, a stretch 0f railroad track divided into sections, a track switch located in an intermediate one of said sections, electrically; controlled track switch operating mechanism, a train, signal receiving .apparatus on the train, remotely controlled apparatus for causing said mechanism to operate the track switch responsive to the entry of said train into a section preceding the one in which the track switch is located, and signaling apparatus for transmitting-distinctive signals indicativeof the position of the track switch to said train carried signal receiving apparatus during the presence of the train in any of said track sections.

22. In a train operating system, a stretch of I circuit associated with the stretch of track and adapted to connect the telephone sets for intercommunication, signaling apparatus associated with the track switch, and means including said signaling apparatus for transmitting distinctive signals indicative of the position of the track switch over said trackwa'y circuit to the telephone sets on the train.

23. In a train operating system, a stretch of railroad track, a closed electrical circuit associated with the track and adapted to co-operate with telephone apparatus carried by trains operating over the track, a wayside station, a line over the track carries a two winding inductor in inductive relation with the circuit, the combination comprising a transmitter, a receiver, an amplifier having input and output leads, a two-position switch, circuit connections completed by said switch in one position for connecting the amplifier input and output leads to the transmitter and to one inductor winding, respectively,

and circuit connections completed by said switch in the other position for connecting the amplifier input and output leads to both inductor windings and to the receiver, respectively.

25. In a train operating system, a stretch oi track for a train, a track switch including the rails of said stretch, a wayside circuit in said stretch of track, a plurality of normally inactive sources of I signaling current, means automatically operative for rendering said current sources active responsive to, a train approaching said stretch of track, means for maintaining the activity of said current sources responsive to the train remaining in said stretch of track, means ior'connecting any one of said sources to said circuit, said last means being controlled by the position of said track switch, and receiver means on said train in inductive relation with said wayside circuit responsive to said current to indicate the position oi. said switch by a repeated audible signal.

26. In a railway train operating system, a stretch of railway track, a train in said stretch, a plurality of normally electrically separate intermediate circuits associated with said stretch, each for conveying electric current and one including the track rails in multiple as one side of said circuit, and means associated with said stretchand controlled by the train for conductively connecting said one circuit with an adjoining intermediate circuit.

'27. In a train operating system, a stretch of railway line, a train in said stretch, running rails for the train, a track switch in said stretch, a circuit including said running rails in said stretch, a normally inactive source of electric current, means associated with said circuit controlled jointly by said switch and said train for connecting said current source to said circuit and for rendering said source effective to deliver current to the circuit, and receiver means on said train in electrical relation with said circuit and respdnsive to said current.

28. In a train operating system, a stretch oi track for a train, a track switch in said stretch, a wayside station, mechanism for operating said switch, means cooperatively controlled by said mechanism, a wayside circuit in said stretch,

. electric current in said wayside circuit controlled by the position of said switch, and receiver means on-said train in inductive relation with said wayside circuit and responsive to said current to indicate the position of said switch.

29. In a trackway system for transmitting communication signals to and from a railway train, in combination, a stretch of track for the train, a first section and a second section in said stretch, a trackway circuit for said first section comprising the two track rails of the section and electric conducting means connected to each of the rails at each end of the section, a trackway circuit for the second'section comprising a conductor along said track and a return conductor associated therewith, and means controlled by the train in moving from one to the other of said sections for connecting said circuits together.

30. In a train operating system, the combination of a stretch of track including a track switch, electrically operated mechanism for opening and closing said switch, a wayside station remote from said track'switch, a switching device asso-- device to its "oiP position, and a train controlled relay operatively associated with said stretch of track forautomatically completing said operating circuit.

31. In a train operating system, the combination of a stretch of railroad track including a track switch, a power operated mechanism for opening and closing the track switch, a local circuit for supplying energy to operate said mechanism, said circuit having at least two normally open points, a wayside station remote from said track switch, a wayside circuit extending from said station to said track switch, a switching device connected with said wayside circuit and associated with the local circuit, instrumentalities in the wayside station adapted to be operated to send out electric current of a prescribed character to which only said switching device is responsive to close said local circuit at one point, said closure continuing until said instrumentalities are again operated, means operable by a train approaching said'track switch for closing another point in said local circuit to complete the circuit whereby energy-1's supplied to said mechanism to open the track switch, and means operative after the train has passed over the track switch for automatically closing the switch.

32. In a system for transmitting distinctive signals from a trackway location to a remote station, the combination of a stretch of track at said trackway location, a local circuit at said trackway location, a generator of electric signal current of distinctive character at said trackway location, a track circuit for the stretch of track, means in said track circuit operative in response to a train entering said stretch of track for initiating the operation of said generator to establish a flow of said distinctive current in said 1 wayside line extending from said trackway location to a remote station, means for connecting the other winding of said transformer to said line whereby said distinctive current is transmitted over the line to said station, and means connected with said line at said station operative to produce a distinctive signal under control of the current transmitted over said line.

33. In a train operating system, a stretch of track-for a train, rails for the train to run on, a track switch in said stretch, a circuit including the running rails in said stretch, electric current of distinctive character in said circuit controlled by the position of the track switch, and,

communication means, including telephone sets at two different points on said train for the transmission and reception of electric communication signals via said circuit, said sets being responsive to said current of distinctive character to give a signal on said train.

34. In aQtrain' operating system, a stretch of track for a train, a track switch in said stretch, means under the control of the train in its approach to the track. switch for opening said switch, means under the control of the train after it has passed over the switch for closing the switch, a wayside circuit in said stretch, electric current in said wayside circuit controlled by each position of the track switch and of a different character for each of said positions, and receiver means on said train in electrical relation with said wayside circuit and responsive to said. current to indicate the position of the track switch as the train approaches said switch and after the train leaves said switch.

35. In a train operating system, a stretch of track containing a train, a track switch in said stretch adapted to be operated to either an open or a closed position, a wayside circuit for said stretch, means operative to cause a distinctive electric current to flow in said wayside circuit corresponding to each of the positions of said trackswitch, a circuit carried on said train in electrical relation with said wayside circuit, and a receiver in said train carried circuit responsive to the electric current in said wayside circuit to tive current generator, circuits controlled from' said wayside station for rendering said generator active, and means operative in accordance with the position of said switch for connecting said generator to said wayside circuit.

37. In a train operating system, a stretch of track for atrain, a track switch in said stretch,

mechanism for operating said switch, means as-" sociated with said stretch for controlling the operation of said mechanism, a wayside circuit for said stretch, electric current in said circuit controlled by the position of said switch, and

receiver means on said train in electrical relation-with said wayside circuit and responsive to said current to indicate'on said train by an audiblesignal the position of said switch for either direction of travel of said train.

38. In a train operating system, the combination with a stretch of track and a train on the track, of a. track switch in said stretch operable -'to either an open or closed position, a wayside circuit for said stretch of track, means at said switch controlled by the train for generating an electrical current of distinctive character to flow in said circuit when the track switch is in one position, and means on the train in electrical relation with said circuit responsive to said current for indicating the position of the switch.

39. In a -train operating system, having a stretch of railroad track provided with an electric circuit cooperating with two conductors caroutput leads respectively to. one of said con- -ductorsand to the transmitter, and circuit connections completed by said switching contacts in another position for connecting said input and output leads respectively to the other of said conductors and to said receiver.

40. In an electrical transmitting and receiving system, including a stretch of railroad track provided with an intermediate circuit of which the running rails of the track form a part, and in which the running rails are arranged for cooperation with a pair of circuits carried by a vehicle running on the'track, one oi said vehicle carried circuits being arranged to transmit electric current to the rails in parallel and the other of said vehicle carried circuits being arranged to receive electric currents flowing in the rails in parallel, the combination of a transmitter, a receiver, an amplifier having input and output leads, switching contacts having a plurality of positions, electrical connections completed by said switching contacts in one position for connecting' said input and output leads respectively to one of said vehicle carried circuits and to the transmitter, andelectrical connections completedby said switching contacts in another position i for connecting the said input and output leads respectively to the other of said vehicle carried circuits and said receiver.

41, In an electrical transmitting and receiving system for railways, the combination of a section of railway track, a vehicle in the section, an intermediate circuit for the section located on the wayside, a transmitter of electric current and a receiver responsive to electric current both on the vehicle, and two electrically separate circuits on the vehicle, each of said circuits being in electrical relation with said intermediate circuit, one of said two circuits beingarranged for connection with said transmitter to send electric currents into the intermediate circuit and. the other of said two circuits being arranged for connection with said receiver for receiving electric current from the intermediate circuit.

ARCHIBALD G. SHAVER.

CERTIFICATE OF CORRECTION. Patent N01; 2,12L u55. I July 19, 195 ARCHIBALD e; SHAVER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiringcorrection as follows: Page 11, first column, line 3 57, claim 2, strike out the Word "loop"; same page, second column, line claim '7, strike out "loop"; and lines ll and 15, same claim, strike out the words "the circuit of" psge 12, second column, line 50, claim 20, for "response" read responsive; page 15, first column, lines 35 and 56, claim 25," for the words "including the rails of said stretch, a w ayside circuit in" read in said stretch, awayside circuit including the rails of; 'and that the said Letters Patent shouldbe read with this correction therein that the same may conform to the ,record of the case in the Patent Officeo v I Signed and sealed this 15th day of November, A, D. 1958. I

Henry Van Arsdale I Acting Commissioner of Patents. 

